Acne (also known as whelk, acne vulgaris, pimple), is a common skin disease which can cause inflammation of human skin sebaceous glands or hair follicles. Spine-shape papules, from which white or creamy white broken rice like juice can be squeezed out, are formed in local lesions. The development of acne is mainly related to the factors, such as excessive sebum secretion, the duct clog of folliculosebaceous, bacteria infections and inflammation reactions. After people enter into their adolescence, the level of androgen, especially testosterone, is increased rapidly, promoting development of sebaceous glands and a large secretion of sebum. At the meantime, the abnormal follicular keratosis of the sebaceous gland ducts causes the clog of ducts, dyssebacia and the formation of keratotic plug (i.e. micro-acne). Various microbes, especially Propionibacterium acnes, overgrow in hair follicle. The lipases generated by Propionibacterium acnes degrade the sebum into free fatty acids, promote the chemotaxis of inflammatory cells and mediators, and finally induce and aggravate inflammation.
Acne often occurs in young people, in both sexes. It is more commonly found in male than in female, but the age of onset in female is earlier than in male. Acne occurs mostly in face, forehead, cheek and nasolabial fold, next in chest, back and shoulder. Usually, the skin damage caused by acne does not have subjective symptom. Pain may be accompanied under severe inflammation reactions. Acne can be classified into acne, papule, pustule and nodular cyst. Acne affects 80-90% of teenagers. After adolescence, acnes often can be abated automatically or cured, except that acne persists in some patients into their thirties. Although acne has a tendency of self-healing, the acnes themselves and scars caused by the acnes without timely treatment may severely affect the life quality of patient and cause mental pressure and financial burden of patients. Attentions should be paid to these problems.
There are six common treatment methods of acne, including:    (1) Drugs for local and external application: tretinoin (tretinoin cream, adapalene gel, tazarotene gel), benzoyl peroxide, antibiotics (clindamycin, erythromycin, chloramphenicol, etc.), azelaic acid, sulfur lotion, etc.;    (2) Oral antibiotics: the first choice is tetracyclines (minocycline, doxycycline, etc.); secondary choice is macrolides (erythromycin); antibiotics which are used for systemic infection treatment, such as levofloxacin, should be avoided. The duration of antibiotic treatment is usually 6-12 weeks.    (3) Oral isotretinoin: for severe acne, oral isotretinoin is the standard treatment and also the most effective treatment so far. The course treatment endpoint is the minimal accumulated dose of 60 mg/kg.    (4) Antiandrogen treatment: for example, oral contraceptive compound cyproterone acetate tablets (trade name: Diane-35), is suitable for female patients of moderate and severe acne. For female patients who have symptoms of high level of androgen (such as hirsutism, seborrhoeia, etc.), polycystic ovary syndrome, late-onset acne and those whose acne becomes intense before their menstrual period, oral contraceptives can also be taken into consideration.    (5) Oral glucocorticoid: it is mainly used for fulminant acne or acne conglobata. The treatments follow the principle of short term, small dose and combination with other treatments.    (6) Others: for the patient who is intolerant to the drug or unwilling to accept drug treatment, physical therapy can also be considered, such as photodynamic therapy (PDT), fruit acid therapy, laser therapy, etc.
The acne treatments should be divided into different stages: stage 1, usually local treatment is adopted and external administration of tretinoins are preferred; stage 2, the combinations of external administration of tretinoins and benzoyl peroxide or antibiotics are used, and oral antibiotics are combined if needed; stage 3, usually combination treatments are needed and the combinations of oral antibiotics with external use benzoyl peroxide and/or tretinoins are first choice; for female patients with indications, antiandrogen treatment may also be taken into consideration. Stage 4, oral isotretinoin is the most effective treatment and can be used as a first-line therapy. For the patients who have inflammatory papules and more pustules, the combination of antibiotic and external benzoyl peroxide can also be applied systemically. After the skin damage is improved obviously, the oral isotretinoin is then applied for sequential treatment.
However, at present, western medicines occupy the main portion of the drug market for acne treatment. Although the western medicines can achieve the effect of acne removing, they have relatively obvious side-effects. So they are not suitable for long-term use and the dose thereof should not be too high. For people from adolescent to adult phase who have frequent and repeating acne occurrences, the acne-removing products which are natural and gentle, with less side-effects and suitable for long-term use are needed.